wtw AmmoLyt 700 IQ, Руководство по эксплуатации

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AmmoLyt
®
700 IQ Calibration and measuring
4 - 23 ba75353e05 03/2006
Potassium
compensation for
measurements
The function, Potassium compens. , should always be used if the con-
centration of the interfering ion causes the measurement signal to
leave the range of the required accuracy. To avoid calibration and
measuring errors, we recommend to
!
routinely determine the potassium contents
!
switch on the Potassium compens. function
!
enter the potassium content.
The more the actual potassium content deviates from the value entered
for the potassium compensation, the more the displayed measured
value deviates from the current ammonium content.
Fig. 4-8 shows the interrelationship of real and displayed
NH4-N value for different potassium contents. The characteristic curve
with the optimum potassium compensation corresponds to the charac-
teristic curve without any potassium content.
Fig. 4-8 Influence of potassium on the measured ammonium value
4.2.3 Further influences on the measured value
Greases, oils, certain tensides and similar substances can shorten the
operational lifetime of the AmmoLyt
®
NHA/AT exchange electrode.
Therefore, they should not be present in the test sample.
real c (NH4-N) [mg/l]
c (NH4-N) [mg/l]
displayed by AmmoLyt 700 IQ
0.1 1 10
100
1000
0.1
10
100
1000
1
.
0 mg/l K
+
10 mg/l K
+
50 mg/l K
+